Method for controlling a circulation pump in an installation comprising at least two circulation circuits

Abstract

A method controls a circulation pump (1) in an installation with at least two circulation circuits (3, 4), with which the circulation pump (1) is integrated by way of a switch-over valve (2) into the one or the other circulation circuit (3 or 4) depending on the switched position. The pump (1) is activated differently depending on the switched position of the switch-over valve (2). The switch-over procedure is detected by way of determining the pressure course and/or the flow rate course in the pump (1) or an electrical variable which is dependent thereon, of the motor driving the pump, and the pump (1) is operated in another manner accordingly.

The invention claimed is: 
     
       1. A method for controlling a circulation pump in an installation with at least two circulation circuits, with which the circulation pump is integrated by way of a switch-over valve into one or another of the circulation circuits depending on a switched position, the method comprising the steps of:
 operating the pump in a first mode depending on the switched position of the switch-over valve; 
 detecting a switch-over procedure of the switch-over valve based on at least one of a pressure course in the pump, a flow rate course in the pump and an electrical variable which is dependent thereon of the motor driving the pump; and 
 operating the pump in a second mode upon detecting the switch-over procedure. 
 
     
     
       2. A method according to  claim 1 , wherein the switched position of the switch-over valve is detected by way of determining at least one of the pressure course, the flow rate course in the pump and the electrical variable of the motor which is dependent thereon. 
     
     
       3. A method according to  claim 2 , wherein the circulation pump is arranged in a heating installation with two heating circuits as the circulation circuits, one of the heating circuits being for service water heating and one of the heating circuits being for room heating, in which installation a primary heat exchanger is conductively connected to the one or the other heating circuit by way of a switch-over valve. 
     
     
       4. A method according to  claim 1 , wherein at least one of the pressure course, the flow rate course in the pump and the electrical variable dependent thereon, of the motor, is continuously detected. 
     
     
       5. A method according to  claim 1 , wherein the switch-over procedure is determined by way of at least one of the pressure course, the flow rate course and the electrical variable of the motor dependent thereon at least one of during the switch-over procedure, directly before the switch-over procedure and after the switch-over procedure. 
     
     
       6. A method according to  claim 1 , wherein the switched position is determined by way of at least one of the pressure course, the flow rate course and the electrical variable of the motor dependent thereon between temporally consecutive switch-over procedures. 
     
     
       7. A method according to  claim 1 , wherein the pressure course or flow rate course is compared with predetermined values for at least one of the switch-over procedure and the switched position, and the at least one of the switch-over procedure and the switched position is determined by way of the comparison. 
     
     
       8. A method according to  claim 1 , wherein the switched position is monitored by way of the pressure course or of the flow rate course or of an electrical variable of the motor which is dependent thereon, and that a switch-over is carried out automatically in the control given a determining of a switched position which is different from a predetermined switched position in the control. 
     
     
       9. A method according to  claim 1 , wherein the switched position for service water heating is ascertained given constant values. 
     
     
       10. A method according to  claim 1 , wherein the switched position for room heating is ascertained given changing values. 
     
     
       11. A circulation pump assembly comprising:
 a speed-controllable electric motor; 
 a centrifugal pump driven by the electric motor pump being integrated into an installation with one or another of at least two circulation circuits by way of a switch-over valve depending on a switched position for delivery into one circulation circuit; and 
 a controller for the speed control of the motor, wherein the controller comprises control and electronics configured for: 
 operating the pump in a first mode depending on the switched position of the switch-over valve; 
 detecting a switch-over procedure of the switch-over valve based on at least one of a pressure course, a flow rate course in the pump and an electrical variable which is dependent thereon of the motor driving the pump; and 
 operating the pump in a second mode upon detecting the switch-over procedure. 
 
     
     
       12. A circulation pump assembly according to  claim 11 , wherein the centrifugal pump is a heating circulation pump and that one circulation circuit is a heating circuit for room heating, and the other circulation circuit is a heating circuit for service water heating. 
     
     
       13. A circulation pump assembly according to  claim 11 , wherein the controller comprises software. 
     
     
       14. A circulation pump assembly according to  claim 11 , wherein the controller monitors the flow rate course or electrical or hydraulic variables dependent thereon, in regulated operating conditions as well as in unregulated operating conditions of the pump. 
     
     
       15. A circulation pump assembly comprising:
 a speed-controllable electric motor; 
 a centrifugal pump driven by the electric motor being integrated into an installation with one or another of at least two circulation circuits by way of a switch-over valve depending on a switched position for delivery into one circulation circuit; and 
 a frequency controller comprising control and regulation electronics configured to: 
 operate the pump in a first mode depending on the switched position of the switch-over valve; 
 detect a switch-over procedure of the switch-over valve based on at least a flow rate of the pump; and 
 operate the pump in a second mode upon detecting the switch-over procedure. 
 
     
     
       16. A circulation pump according to  claim 15 , wherein the control and regulation electronics compares a pressure course or a flow rate course with predetermined characteristic values for at least one of the switch-over procedure and the switched position, and the at least one of the switch-over procedure and the switched position is determined by way of the comparison. 
     
     
       17. A circulation pump assembly according to  claim 15 , wherein the control and regulation electronics monitors the flow rate course or electrical or hydraulic variables dependent thereon, in regulated operating conditions as well as in unregulated operating conditions of the pump.